create monad and functor interfaces

common/api/src/main/java/com/dfsek/terra/api/util/function/functor/Functor.java

@@ -0,0 +1,8 @@
+package com.dfsek.terra.api.util.function.functor;
+
+import java.util.function.Function;
+
+
+public interface Functor<T> {
+    <U> Functor<U> map(Function<T, U> map);
+}

common/api/src/main/java/com/dfsek/terra/api/util/function/monad/Monad.java

@@ -0,0 +1,8 @@
+package com.dfsek.terra.api.util.function.monad;
+
+import java.util.function.Function;
+
+
+public interface Monad<T> {
+    <U> Monad<U> bind(Function<T, Monad<U>> map);
+}